Liquid Dye Testing

ATRONA is accredited to perform LDP testing. Liquid Dye Penetrant testing is conducted at ATRONA as a tool for failure analysis. We also perform this type of NDT procedure on production components to determine surface indications on non magnetic steels and non ferrous alloys. Testing is conducted in accordance with ASTM E165.

DYE PENETRANT INSPECTION (DPI) ALSO CALLED LIQUID PENETRANT INSPECTION (LPI), is a widely applied and low-cost inspection method used to locate surface discontinuities or other indications in all non-porous materials (metals, plastics, or ceramics). Penetrant may be applied to all non-ferrous materials, but for inspection of ferrous components Magnetic Particle Inspection (MPI) is preferred for its subsurface detection capability. LPI is used to detect casting and forging defects, cracks, and leaks in new products, and fatigue cracks on in-service components. Liquid Penetrant Testing (PT) and inspection is a non- destructive method of revealing discontinuities that are open to the surfaces of solid and essentially nonporous materials. Indications of a wide spectrum of flaw sizes can be found regardless of the configuration of the work piece and regardless of flaw orientations. Liquid penetrants seep into various types of minute surface openings by capillary action. Because of this, the process is well suited to the detection of all types of surface defects such as:

  • Cracks
  • Seams
  • Porosity
  • Laps
  • Lamination
  • Cold Shuts

Liquid Penetrant Testing is extensively used for the evaluation of wrought and cast products of both ferrous and nonferrous metals, power metallurgy parts, ceramics, plastics, and glass objects. Because of the vast differences among applications for penetrant inspection. Liquid dye penetrant is a perfect method for examining for stress-corrosion and fatigue cracks that are insidious, usually there is very little or no warning of their presence. This is why it is very important to provide early detection on such structures as cranes, bridges, vessels, piping, where there is risk of possible hard economic consequences, injury or loss of life.


Acredited to perform LDP testing per ASTM E165. Conducted at our facility or yours.

Liquid Dye Testing